contrib/file/readelf.c

   1 /*
   2  * Copyright (c) Christos Zoulas 2003.
   3  * All Rights Reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice immediately at the beginning of the file, without modification,
  10  *    this list of conditions, and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  18  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
  19  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  25  * SUCH DAMAGE.
  26  */
  27 #include "file.h"
  28
  29 #ifndef lint
  30 FILE_RCSID("@(#)$File: readelf.c,v 1.90 2011/08/23 08:01:12 christos Exp $")
  31 #endif
  32
  33 #ifdef BUILTIN_ELF
  34 #include <string.h>
  35 #include <ctype.h>
  36 #include <stdlib.h>
  37 #ifdef HAVE_UNISTD_H
  38 #include <unistd.h>
  39 #endif
  40
  41 #include "readelf.h"
  42 #include "magic.h"
  43
  44 #ifdef  ELFCORE
  45 private int dophn_core(struct magic_set *, int, int, int, off_t, int, size_t,
  46     off_t, int *);
  47 #endif
  48 private int dophn_exec(struct magic_set *, int, int, int, off_t, int, size_t,
  49     off_t, int *, int);
  50 private int doshn(struct magic_set *, int, int, int, off_t, int, size_t,
  51     off_t, int *, int);
  52 private size_t donote(struct magic_set *, void *, size_t, size_t, int,
  53     int, size_t, int *);
  54
  55 #define ELF_ALIGN(a)    ((((a) + align - 1) / align) * align)
  56
  57 #define isquote(c) (strchr("'\"`", (c)) != NULL)
  58
  59 private uint16_t getu16(int, uint16_t);
  60 private uint32_t getu32(int, uint32_t);
  61 private uint64_t getu64(int, uint64_t);
  62
  63 #define MAX_PHNUM       256
  64 #define MAX_SHNUM       1024
  65
  66 private int
  67 toomany(struct magic_set *ms, const char *name, uint16_t num)
  68 {
  69         if (file_printf(ms, ", too many %s header sections (%u)", name, num
  70             ) == -1)
  71                 return -1;
  72         return 0;
  73 }
  74
  75 private uint16_t
  76 getu16(int swap, uint16_t value)
  77 {
  78         union {
  79                 uint16_t ui;
  80                 char c[2];
  81         } retval, tmpval;
  82
  83         if (swap) {
  84                 tmpval.ui = value;
  85
  86                 retval.c[0] = tmpval.c[1];
  87                 retval.c[1] = tmpval.c[0];
  88
  89                 return retval.ui;
  90         } else
  91                 return value;
  92 }
  93
  94 private uint32_t
  95 getu32(int swap, uint32_t value)
  96 {
  97         union {
  98                 uint32_t ui;
  99                 char c[4];
 100         } retval, tmpval;
 101
 102         if (swap) {
 103                 tmpval.ui = value;
 104
 105                 retval.c[0] = tmpval.c[3];
 106                 retval.c[1] = tmpval.c[2];
 107                 retval.c[2] = tmpval.c[1];
 108                 retval.c[3] = tmpval.c[0];
 109
 110                 return retval.ui;
 111         } else
 112                 return value;
 113 }
 114
 115 private uint64_t
 116 getu64(int swap, uint64_t value)
 117 {
 118         union {
 119                 uint64_t ui;
 120                 char c[8];
 121         } retval, tmpval;
 122
 123         if (swap) {
 124                 tmpval.ui = value;
 125
 126                 retval.c[0] = tmpval.c[7];
 127                 retval.c[1] = tmpval.c[6];
 128                 retval.c[2] = tmpval.c[5];
 129                 retval.c[3] = tmpval.c[4];
 130                 retval.c[4] = tmpval.c[3];
 131                 retval.c[5] = tmpval.c[2];
 132                 retval.c[6] = tmpval.c[1];
 133                 retval.c[7] = tmpval.c[0];
 134
 135                 return retval.ui;
 136         } else
 137                 return value;
 138 }
 139
 140 #define elf_getu16(swap, value) getu16(swap, value)
 141 #define elf_getu32(swap, value) getu32(swap, value)
 142 #ifdef USE_ARRAY_FOR_64BIT_TYPES
 143 # define elf_getu64(swap, array) \
 144         ((swap ? ((uint64_t)elf_getu32(swap, array[0])) << 32 : elf_getu32(swap, array[0])) + \
 145          (swap ? elf_getu32(swap, array[1]) : ((uint64_t)elf_getu32(swap, array[1]) << 32)))
 146 #else
 147 # define elf_getu64(swap, value) getu64(swap, value)
 148 #endif
 149
 150 #define xsh_addr        (clazz == ELFCLASS32                    \
 151                          ? (void *) &sh32                       \
 152                          : (void *) &sh64)
 153 #define xsh_sizeof      (clazz == ELFCLASS32                    \
 154                          ? sizeof sh32                          \
 155                          : sizeof sh64)
 156 #define xsh_size        (clazz == ELFCLASS32                    \
 157                          ? elf_getu32(swap, sh32.sh_size)       \
 158                          : elf_getu64(swap, sh64.sh_size))
 159 #define xsh_offset      (off_t)(clazz == ELFCLASS32             \
 160                          ? elf_getu32(swap, sh32.sh_offset)     \
 161                          : elf_getu64(swap, sh64.sh_offset))
 162 #define xsh_type        (clazz == ELFCLASS32                    \
 163                          ? elf_getu32(swap, sh32.sh_type)       \
 164                          : elf_getu32(swap, sh64.sh_type))
 165 #define xph_addr        (clazz == ELFCLASS32                    \
 166                          ? (void *) &ph32                       \
 167                          : (void *) &ph64)
 168 #define xph_sizeof      (clazz == ELFCLASS32                    \
 169                          ? sizeof ph32                          \
 170                          : sizeof ph64)
 171 #define xph_type        (clazz == ELFCLASS32                    \
 172                          ? elf_getu32(swap, ph32.p_type)        \
 173                          : elf_getu32(swap, ph64.p_type))
 174 #define xph_offset      (off_t)(clazz == ELFCLASS32             \
 175                          ? elf_getu32(swap, ph32.p_offset)      \
 176                          : elf_getu64(swap, ph64.p_offset))
 177 #define xph_align       (size_t)((clazz == ELFCLASS32           \
 178                          ? (off_t) (ph32.p_align ?              \
 179                             elf_getu32(swap, ph32.p_align) : 4) \
 180                          : (off_t) (ph64.p_align ?              \
 181                             elf_getu64(swap, ph64.p_align) : 4)))
 182 #define xph_filesz      (size_t)((clazz == ELFCLASS32           \
 183                          ? elf_getu32(swap, ph32.p_filesz)      \
 184                          : elf_getu64(swap, ph64.p_filesz)))
 185 #define xnh_addr        (clazz == ELFCLASS32                    \
 186                          ? (void *) &nh32                       \
 187                          : (void *) &nh64)
 188 #define xph_memsz       (size_t)((clazz == ELFCLASS32           \
 189                          ? elf_getu32(swap, ph32.p_memsz)       \
 190                          : elf_getu64(swap, ph64.p_memsz)))
 191 #define xnh_sizeof      (clazz == ELFCLASS32                    \
 192                          ? sizeof nh32                          \
 193                          : sizeof nh64)
 194 #define xnh_type        (clazz == ELFCLASS32                    \
 195                          ? elf_getu32(swap, nh32.n_type)        \
 196                          : elf_getu32(swap, nh64.n_type))
 197 #define xnh_namesz      (clazz == ELFCLASS32                    \
 198                          ? elf_getu32(swap, nh32.n_namesz)      \
 199                          : elf_getu32(swap, nh64.n_namesz))
 200 #define xnh_descsz      (clazz == ELFCLASS32                    \
 201                          ? elf_getu32(swap, nh32.n_descsz)      \
 202                          : elf_getu32(swap, nh64.n_descsz))
 203 #define prpsoffsets(i)  (clazz == ELFCLASS32                    \
 204                          ? prpsoffsets32[i]                     \
 205                          : prpsoffsets64[i])
 206 #define xcap_addr       (clazz == ELFCLASS32                    \
 207                          ? (void *) &cap32                      \
 208                          : (void *) &cap64)
 209 #define xcap_sizeof     (clazz == ELFCLASS32                    \
 210                          ? sizeof cap32                         \
 211                          : sizeof cap64)
 212 #define xcap_tag        (clazz == ELFCLASS32                    \
 213                          ? elf_getu32(swap, cap32.c_tag)        \
 214                          : elf_getu64(swap, cap64.c_tag))
 215 #define xcap_val        (clazz == ELFCLASS32                    \
 216                          ? elf_getu32(swap, cap32.c_un.c_val)   \
 217                          : elf_getu64(swap, cap64.c_un.c_val))
 218
 219 #ifdef ELFCORE
 220 /*
 221  * Try larger offsets first to avoid false matches
 222  * from earlier data that happen to look like strings.
 223  */
 224 static const size_t     prpsoffsets32[] = {
 225 #ifdef USE_NT_PSINFO
 226         104,            /* SunOS 5.x (command line) */
 227         88,             /* SunOS 5.x (short name) */
 228 #endif /* USE_NT_PSINFO */
 229
 230         100,            /* SunOS 5.x (command line) */
 231         84,             /* SunOS 5.x (short name) */
 232
 233         44,             /* Linux (command line) */
 234         28,             /* Linux 2.0.36 (short name) */
 235
 236         8,              /* FreeBSD */
 237 };
 238
 239 static const size_t     prpsoffsets64[] = {
 240 #ifdef USE_NT_PSINFO
 241         152,            /* SunOS 5.x (command line) */
 242         136,            /* SunOS 5.x (short name) */
 243 #endif /* USE_NT_PSINFO */
 244
 245         136,            /* SunOS 5.x, 64-bit (command line) */
 246         120,            /* SunOS 5.x, 64-bit (short name) */
 247
 248         56,             /* Linux (command line) */
 249         40,             /* Linux (tested on core from 2.4.x, short name) */
 250
 251         16,             /* FreeBSD, 64-bit */
 252 };
 253
 254 #define NOFFSETS32      (sizeof prpsoffsets32 / sizeof prpsoffsets32[0])
 255 #define NOFFSETS64      (sizeof prpsoffsets64 / sizeof prpsoffsets64[0])
 256
 257 #define NOFFSETS        (clazz == ELFCLASS32 ? NOFFSETS32 : NOFFSETS64)
 258
 259 /*
 260  * Look through the program headers of an executable image, searching
 261  * for a PT_NOTE section of type NT_PRPSINFO, with a name "CORE" or
 262  * "FreeBSD"; if one is found, try looking in various places in its
 263  * contents for a 16-character string containing only printable
 264  * characters - if found, that string should be the name of the program
 265  * that dropped core.  Note: right after that 16-character string is,
 266  * at least in SunOS 5.x (and possibly other SVR4-flavored systems) and
 267  * Linux, a longer string (80 characters, in 5.x, probably other
 268  * SVR4-flavored systems, and Linux) containing the start of the
 269  * command line for that program.
 270  *
 271  * SunOS 5.x core files contain two PT_NOTE sections, with the types
 272  * NT_PRPSINFO (old) and NT_PSINFO (new).  These structs contain the
 273  * same info about the command name and command line, so it probably
 274  * isn't worthwhile to look for NT_PSINFO, but the offsets are provided
 275  * above (see USE_NT_PSINFO), in case we ever decide to do so.  The
 276  * NT_PRPSINFO and NT_PSINFO sections are always in order and adjacent;
 277  * the SunOS 5.x file command relies on this (and prefers the latter).
 278  *
 279  * The signal number probably appears in a section of type NT_PRSTATUS,
 280  * but that's also rather OS-dependent, in ways that are harder to
 281  * dissect with heuristics, so I'm not bothering with the signal number.
 282  * (I suppose the signal number could be of interest in situations where
 283  * you don't have the binary of the program that dropped core; if you
 284  * *do* have that binary, the debugger will probably tell you what
 285  * signal it was.)
 286  */
 287
 288 #define OS_STYLE_SVR4           0
 289 #define OS_STYLE_FREEBSD        1
 290 #define OS_STYLE_NETBSD         2
 291
 292 private const char os_style_names[][8] = {
 293         "SVR4",
 294         "FreeBSD",
 295         "NetBSD",
 296 };
 297
 298 #define FLAGS_DID_CORE          0x01
 299 #define FLAGS_DID_NOTE          0x02
 300 #define FLAGS_DID_BUILD_ID      0x04
 301 #define FLAGS_DID_CORE_STYLE    0x08
 302 #define FLAGS_IS_CORE           0x10
 303
 304 private int
 305 dophn_core(struct magic_set *ms, int clazz, int swap, int fd, off_t off,
 306     int num, size_t size, off_t fsize, int *flags)
 307 {
 308         Elf32_Phdr ph32;
 309         Elf64_Phdr ph64;
 310         size_t offset;
 311         unsigned char nbuf[BUFSIZ];
 312         ssize_t bufsize;
 313
 314         if (size != xph_sizeof) {
 315                 if (file_printf(ms, ", corrupted program header size") == -1)
 316                         return -1;
 317                 return 0;
 318         }
 319
 320         /*
 321          * Loop through all the program headers.
 322          */
 323         for ( ; num; num--) {
 324                 if (lseek(fd, off, SEEK_SET) == (off_t)-1) {
 325                         file_badseek(ms);
 326                         return -1;
 327                 }
 328                 if (read(fd, xph_addr, xph_sizeof) == -1) {
 329                         file_badread(ms);
 330                         return -1;
 331                 }
 332                 off += size;
 333
 334                 if (xph_offset > fsize) {
 335                         /* Perhaps warn here */
 336                         continue;
 337                 }
 338
 339                 if (xph_type != PT_NOTE)
 340                         continue;
 341
 342                 /*
 343                  * This is a PT_NOTE section; loop through all the notes
 344                  * in the section.
 345                  */
 346                 if (lseek(fd, xph_offset, SEEK_SET) == (off_t)-1) {
 347                         file_badseek(ms);
 348                         return -1;
 349                 }
 350                 bufsize = read(fd, nbuf,
 351                     ((xph_filesz < sizeof(nbuf)) ? xph_filesz : sizeof(nbuf)));
 352                 if (bufsize == -1) {
 353                         file_badread(ms);
 354                         return -1;
 355                 }
 356                 offset = 0;
 357                 for (;;) {
 358                         if (offset >= (size_t)bufsize)
 359                                 break;
 360                         offset = donote(ms, nbuf, offset, (size_t)bufsize,
 361                             clazz, swap, 4, flags);
 362                         if (offset == 0)
 363                                 break;
 364
 365                 }
 366         }
 367         return 0;
 368 }
 369 #endif
 370
 371 private size_t
 372 donote(struct magic_set *ms, void *vbuf, size_t offset, size_t size,
 373     int clazz, int swap, size_t align, int *flags)
 374 {
 375         Elf32_Nhdr nh32;
 376         Elf64_Nhdr nh64;
 377         size_t noff, doff;
 378 #ifdef ELFCORE
 379         int os_style = -1;
 380 #endif
 381         uint32_t namesz, descsz;
 382         unsigned char *nbuf = CAST(unsigned char *, vbuf);
 383
 384         (void)memcpy(xnh_addr, &nbuf[offset], xnh_sizeof);
 385         offset += xnh_sizeof;
 386
 387         namesz = xnh_namesz;
 388         descsz = xnh_descsz;
 389         if ((namesz == 0) && (descsz == 0)) {
 390                 /*
 391                  * We're out of note headers.
 392                  */
 393                 return (offset >= size) ? offset : size;
 394         }
 395
 396         if (namesz & 0x80000000) {
 397             (void)file_printf(ms, ", bad note name size 0x%lx",
 398                 (unsigned long)namesz);
 399             return 0;
 400         }
 401
 402         if (descsz & 0x80000000) {
 403             (void)file_printf(ms, ", bad note description size 0x%lx",
 404                 (unsigned long)descsz);
 405             return 0;
 406         }
 407
 408
 409         noff = offset;
 410         doff = ELF_ALIGN(offset + namesz);
 411
 412         if (offset + namesz > size) {
 413                 /*
 414                  * We're past the end of the buffer.
 415                  */
 416                 return doff;
 417         }
 418
 419         offset = ELF_ALIGN(doff + descsz);
 420         if (doff + descsz > size) {
 421                 /*
 422                  * We're past the end of the buffer.
 423                  */
 424                 return (offset >= size) ? offset : size;
 425         }
 426
 427         if ((*flags & (FLAGS_DID_NOTE|FLAGS_DID_BUILD_ID)) ==
 428             (FLAGS_DID_NOTE|FLAGS_DID_BUILD_ID))
 429                 goto core;
 430
 431         if (namesz == 4 && strcmp((char *)&nbuf[noff], "GNU") == 0 &&
 432             xnh_type == NT_GNU_VERSION && descsz == 16) {
 433                 uint32_t desc[4];
 434                 (void)memcpy(desc, &nbuf[doff], sizeof(desc));
 435
 436                 if (file_printf(ms, ", for GNU/") == -1)
 437                         return size;
 438                 switch (elf_getu32(swap, desc[0])) {
 439                 case GNU_OS_LINUX:
 440                         if (file_printf(ms, "Linux") == -1)
 441                                 return size;
 442                         break;
 443                 case GNU_OS_HURD:
 444                         if (file_printf(ms, "Hurd") == -1)
 445                                 return size;
 446                         break;
 447                 case GNU_OS_SOLARIS:
 448                         if (file_printf(ms, "Solaris") == -1)
 449                                 return size;
 450                         break;
 451                 case GNU_OS_KFREEBSD:
 452                         if (file_printf(ms, "kFreeBSD") == -1)
 453                                 return size;
 454                         break;
 455                 case GNU_OS_KNETBSD:
 456                         if (file_printf(ms, "kNetBSD") == -1)
 457                                 return size;
 458                         break;
 459                 default:
 460                         if (file_printf(ms, "<unknown>") == -1)
 461                                 return size;
 462                 }
 463                 if (file_printf(ms, " %d.%d.%d", elf_getu32(swap, desc[1]),
 464                     elf_getu32(swap, desc[2]), elf_getu32(swap, desc[3])) == -1)
 465                         return size;
 466                 *flags |= FLAGS_DID_NOTE;
 467                 return size;
 468         }
 469
 470         if (namesz == 4 && strcmp((char *)&nbuf[noff], "GNU") == 0 &&
 471             xnh_type == NT_GNU_BUILD_ID && (descsz == 16 || descsz == 20)) {
 472             uint32_t desc[5], i;
 473             if (file_printf(ms, ", BuildID[%s]=0x", descsz == 16 ? "md5/uuid" :
 474                 "sha1") == -1)
 475                     return size;
 476             (void)memcpy(desc, &nbuf[doff], descsz);
 477             for (i = 0; i < descsz >> 2; i++)
 478                 if (file_printf(ms, "%.8x", desc[i]) == -1)
 479                     return size;
 480             *flags |= FLAGS_DID_BUILD_ID;
 481         }
 482
 483         if (namesz == 7 && strcmp((char *)&nbuf[noff], "NetBSD") == 0 &&
 484             xnh_type == NT_NETBSD_VERSION && descsz == 4) {
 485                 uint32_t desc;
 486                 (void)memcpy(&desc, &nbuf[doff], sizeof(desc));
 487                 desc = elf_getu32(swap, desc);
 488
 489                 if (file_printf(ms, ", for NetBSD") == -1)
 490                         return size;
 491                 /*
 492                  * The version number used to be stuck as 199905, and was thus
 493                  * basically content-free.  Newer versions of NetBSD have fixed
 494                  * this and now use the encoding of __NetBSD_Version__:
 495                  *
 496                  *      MMmmrrpp00
 497                  *
 498                  * M = major version
 499                  * m = minor version
 500                  * r = release ["",A-Z,Z[A-Z] but numeric]
 501                  * p = patchlevel
 502                  */
 503                 if (desc > 100000000U) {
 504                         uint32_t ver_patch = (desc / 100) % 100;
 505                         uint32_t ver_rel = (desc / 10000) % 100;
 506                         uint32_t ver_min = (desc / 1000000) % 100;
 507                         uint32_t ver_maj = desc / 100000000;
 508
 509                         if (file_printf(ms, " %u.%u", ver_maj, ver_min) == -1)
 510                                 return size;
 511                         if (ver_rel == 0 && ver_patch != 0) {
 512                                 if (file_printf(ms, ".%u", ver_patch) == -1)
 513                                         return size;
 514                         } else if (ver_rel != 0) {
 515                                 while (ver_rel > 26) {
 516                                         if (file_printf(ms, "Z") == -1)
 517                                                 return size;
 518                                         ver_rel -= 26;
 519                                 }
 520                                 if (file_printf(ms, "%c", 'A' + ver_rel - 1)
 521                                     == -1)
 522                                         return size;
 523                         }
 524                 }
 525                 *flags |= FLAGS_DID_NOTE;
 526                 return size;
 527         }
 528
 529         if (namesz == 8 && strcmp((char *)&nbuf[noff], "FreeBSD") == 0 &&
 530             xnh_type == NT_FREEBSD_VERSION && descsz == 4) {
 531                 uint32_t desc;
 532                 (void)memcpy(&desc, &nbuf[doff], sizeof(desc));
 533                 desc = elf_getu32(swap, desc);
 534                 if (file_printf(ms, ", for FreeBSD") == -1)
 535                         return size;
 536
 537                 /*
 538                  * Contents is __FreeBSD_version, whose relation to OS
 539                  * versions is defined by a huge table in the Porter's
 540                  * Handbook.  This is the general scheme:
 541                  *
 542                  * Releases:
 543                  *      Mmp000 (before 4.10)
 544                  *      Mmi0p0 (before 5.0)
 545                  *      Mmm0p0
 546                  *
 547                  * Development branches:
 548                  *      Mmpxxx (before 4.6)
 549                  *      Mmp1xx (before 4.10)
 550                  *      Mmi1xx (before 5.0)
 551                  *      M000xx (pre-M.0)
 552                  *      Mmm1xx
 553                  *
 554                  * M = major version
 555                  * m = minor version
 556                  * i = minor version increment (491000 -> 4.10)
 557                  * p = patchlevel
 558                  * x = revision
 559                  *
 560                  * The first release of FreeBSD to use ELF by default
 561                  * was version 3.0.
 562                  */
 563                 if (desc == 460002) {
 564                         if (file_printf(ms, " 4.6.2") == -1)
 565                                 return size;
 566                 } else if (desc < 460100) {
 567                         if (file_printf(ms, " %d.%d", desc / 100000,
 568                             desc / 10000 % 10) == -1)
 569                                 return size;
 570                         if (desc / 1000 % 10 > 0)
 571                                 if (file_printf(ms, ".%d", desc / 1000 % 10)
 572                                     == -1)
 573                                         return size;
 574                         if ((desc % 1000 > 0) || (desc % 100000 == 0))
 575                                 if (file_printf(ms, " (%d)", desc) == -1)
 576                                         return size;
 577                 } else if (desc < 500000) {
 578                         if (file_printf(ms, " %d.%d", desc / 100000,
 579                             desc / 10000 % 10 + desc / 1000 % 10) == -1)
 580                                 return size;
 581                         if (desc / 100 % 10 > 0) {
 582                                 if (file_printf(ms, " (%d)", desc) == -1)
 583                                         return size;
 584                         } else if (desc / 10 % 10 > 0) {
 585                                 if (file_printf(ms, ".%d", desc / 10 % 10)
 586                                     == -1)
 587                                         return size;
 588                         }
 589                 } else {
 590                         if (file_printf(ms, " %d.%d", desc / 100000,
 591                             desc / 1000 % 100) == -1)
 592                                 return size;
 593                         if ((desc / 100 % 10 > 0) ||
 594                             (desc % 100000 / 100 == 0)) {
 595                                 if (file_printf(ms, " (%d)", desc) == -1)
 596                                         return size;
 597                         } else if (desc / 10 % 10 > 0) {
 598                                 if (file_printf(ms, ".%d", desc / 10 % 10)
 599                                     == -1)
 600                                         return size;
 601                         }
 602                 }
 603                 *flags |= FLAGS_DID_NOTE;
 604                 return size;
 605         }
 606
 607         if (namesz == 8 && strcmp((char *)&nbuf[noff], "OpenBSD") == 0 &&
 608             xnh_type == NT_OPENBSD_VERSION && descsz == 4) {
 609                 if (file_printf(ms, ", for OpenBSD") == -1)
 610                         return size;
 611                 /* Content of note is always 0 */
 612                 *flags |= FLAGS_DID_NOTE;
 613                 return size;
 614         }
 615
 616         if (namesz == 10 && strcmp((char *)&nbuf[noff], "DragonFly") == 0 &&
 617             xnh_type == NT_DRAGONFLY_VERSION && descsz == 4) {
 618                 uint32_t desc;
 619                 if (file_printf(ms, ", for DragonFly") == -1)
 620                         return size;
 621                 (void)memcpy(&desc, &nbuf[doff], sizeof(desc));
 622                 desc = elf_getu32(swap, desc);
 623                 if (file_printf(ms, " %d.%d.%d", desc / 100000,
 624                     desc / 10000 % 10, desc % 10000) == -1)
 625                         return size;
 626                 *flags |= FLAGS_DID_NOTE;
 627                 return size;
 628         }
 629
 630 core:
 631         /*
 632          * Sigh.  The 2.0.36 kernel in Debian 2.1, at
 633          * least, doesn't correctly implement name
 634          * sections, in core dumps, as specified by
 635          * the "Program Linking" section of "UNIX(R) System
 636          * V Release 4 Programmer's Guide: ANSI C and
 637          * Programming Support Tools", because my copy
 638          * clearly says "The first 'namesz' bytes in 'name'
 639          * contain a *null-terminated* [emphasis mine]
 640          * character representation of the entry's owner
 641          * or originator", but the 2.0.36 kernel code
 642          * doesn't include the terminating null in the
 643          * name....
 644          */
 645         if ((namesz == 4 && strncmp((char *)&nbuf[noff], "CORE", 4) == 0) ||
 646             (namesz == 5 && strcmp((char *)&nbuf[noff], "CORE") == 0)) {
 647                 os_style = OS_STYLE_SVR4;
 648         }
 649
 650         if ((namesz == 8 && strcmp((char *)&nbuf[noff], "FreeBSD") == 0)) {
 651                 os_style = OS_STYLE_FREEBSD;
 652         }
 653
 654         if ((namesz >= 11 && strncmp((char *)&nbuf[noff], "NetBSD-CORE", 11)
 655             == 0)) {
 656                 os_style = OS_STYLE_NETBSD;
 657         }
 658
 659 #ifdef ELFCORE
 660         if ((*flags & FLAGS_DID_CORE) != 0)
 661                 return size;
 662
 663         if (os_style != -1 && (*flags & FLAGS_DID_CORE_STYLE) == 0) {
 664                 if (file_printf(ms, ", %s-style", os_style_names[os_style])
 665                     == -1)
 666                         return size;
 667                 *flags |= FLAGS_DID_CORE_STYLE;
 668         }
 669
 670         switch (os_style) {
 671         case OS_STYLE_NETBSD:
 672                 if (xnh_type == NT_NETBSD_CORE_PROCINFO) {
 673                         uint32_t signo;
 674                         /*
 675                          * Extract the program name.  It is at
 676                          * offset 0x7c, and is up to 32-bytes,
 677                          * including the terminating NUL.
 678                          */
 679                         if (file_printf(ms, ", from '%.31s'",
 680                             &nbuf[doff + 0x7c]) == -1)
 681                                 return size;
 682
 683                         /*
 684                          * Extract the signal number.  It is at
 685                          * offset 0x08.
 686                          */
 687                         (void)memcpy(&signo, &nbuf[doff + 0x08],
 688                             sizeof(signo));
 689                         if (file_printf(ms, " (signal %u)",
 690                             elf_getu32(swap, signo)) == -1)
 691                                 return size;
 692                         *flags |= FLAGS_DID_CORE;
 693                         return size;
 694                 }
 695                 break;
 696
 697         default:
 698                 if (xnh_type == NT_PRPSINFO && *flags & FLAGS_IS_CORE) {
 699                         size_t i, j;
 700                         unsigned char c;
 701                         /*
 702                          * Extract the program name.  We assume
 703                          * it to be 16 characters (that's what it
 704                          * is in SunOS 5.x and Linux).
 705                          *
 706                          * Unfortunately, it's at a different offset
 707                          * in various OSes, so try multiple offsets.
 708                          * If the characters aren't all printable,
 709                          * reject it.
 710                          */
 711                         for (i = 0; i < NOFFSETS; i++) {
 712                                 unsigned char *cname, *cp;
 713                                 size_t reloffset = prpsoffsets(i);
 714                                 size_t noffset = doff + reloffset;
 715                                 size_t k;
 716                                 for (j = 0; j < 16; j++, noffset++,
 717                                     reloffset++) {
 718                                         /*
 719                                          * Make sure we're not past
 720                                          * the end of the buffer; if
 721                                          * we are, just give up.
 722                                          */
 723                                         if (noffset >= size)
 724                                                 goto tryanother;
 725
 726                                         /*
 727                                          * Make sure we're not past
 728                                          * the end of the contents;
 729                                          * if we are, this obviously
 730                                          * isn't the right offset.
 731                                          */
 732                                         if (reloffset >= descsz)
 733                                                 goto tryanother;
 734
 735                                         c = nbuf[noffset];
 736                                         if (c == '\0') {
 737                                                 /*
 738                                                  * A '\0' at the
 739                                                  * beginning is
 740                                                  * obviously wrong.
 741                                                  * Any other '\0'
 742                                                  * means we're done.
 743                                                  */
 744                                                 if (j == 0)
 745                                                         goto tryanother;
 746                                                 else
 747                                                         break;
 748                                         } else {
 749                                                 /*
 750                                                  * A nonprintable
 751                                                  * character is also
 752                                                  * wrong.
 753                                                  */
 754                                                 if (!isprint(c) || isquote(c))
 755                                                         goto tryanother;
 756                                         }
 757                                 }
 758                                 /*
 759                                  * Well, that worked.
 760                                  */
 761
 762                                 /*
 763                                  * Try next offsets, in case this match is
 764                                  * in the middle of a string.
 765                                  */
 766                                 for (k = i + 1 ; k < NOFFSETS ; k++) {
 767                                         size_t no;
 768                                         int adjust = 1;
 769                                         if (prpsoffsets(k) >= prpsoffsets(i))
 770                                                 continue;
 771                                         for (no = doff + prpsoffsets(k);
 772                                              no < doff + prpsoffsets(i); no++)
 773                                                 adjust = adjust
 774                                                          && isprint(nbuf[no]);
 775                                         if (adjust)
 776                                                 i = k;
 777                                 }
 778
 779                                 cname = (unsigned char *)
 780                                     &nbuf[doff + prpsoffsets(i)];
 781                                 for (cp = cname; *cp && isprint(*cp); cp++)
 782                                         continue;
 783                                 /*
 784                                  * Linux apparently appends a space at the end
 785                                  * of the command line: remove it.
 786                                  */
 787                                 while (cp > cname && isspace(cp[-1]))
 788                                         cp--;
 789                                 if (file_printf(ms, ", from '%.*s'",
 790                                     (int)(cp - cname), cname) == -1)
 791                                         return size;
 792                                 *flags |= FLAGS_DID_CORE;
 793                                 return size;
 794
 795                         tryanother:
 796                                 ;
 797                         }
 798                 }
 799                 break;
 800         }
 801 #endif
 802         return offset;
 803 }
 804
 805 /* SunOS 5.x hardware capability descriptions */
 806 typedef struct cap_desc {
 807         uint64_t cd_mask;
 808         const char *cd_name;
 809 } cap_desc_t;
 810
 811 static const cap_desc_t cap_desc_sparc[] = {
 812         { AV_SPARC_MUL32,               "MUL32" },
 813         { AV_SPARC_DIV32,               "DIV32" },
 814         { AV_SPARC_FSMULD,              "FSMULD" },
 815         { AV_SPARC_V8PLUS,              "V8PLUS" },
 816         { AV_SPARC_POPC,                "POPC" },
 817         { AV_SPARC_VIS,                 "VIS" },
 818         { AV_SPARC_VIS2,                "VIS2" },
 819         { AV_SPARC_ASI_BLK_INIT,        "ASI_BLK_INIT" },
 820         { AV_SPARC_FMAF,                "FMAF" },
 821         { AV_SPARC_FJFMAU,              "FJFMAU" },
 822         { AV_SPARC_IMA,                 "IMA" },
 823         { 0, NULL }
 824 };
 825
 826 static const cap_desc_t cap_desc_386[] = {
 827         { AV_386_FPU,                   "FPU" },
 828         { AV_386_TSC,                   "TSC" },
 829         { AV_386_CX8,                   "CX8" },
 830         { AV_386_SEP,                   "SEP" },
 831         { AV_386_AMD_SYSC,              "AMD_SYSC" },
 832         { AV_386_CMOV,                  "CMOV" },
 833         { AV_386_MMX,                   "MMX" },
 834         { AV_386_AMD_MMX,               "AMD_MMX" },
 835         { AV_386_AMD_3DNow,             "AMD_3DNow" },
 836         { AV_386_AMD_3DNowx,            "AMD_3DNowx" },
 837         { AV_386_FXSR,                  "FXSR" },
 838         { AV_386_SSE,                   "SSE" },
 839         { AV_386_SSE2,                  "SSE2" },
 840         { AV_386_PAUSE,                 "PAUSE" },
 841         { AV_386_SSE3,                  "SSE3" },
 842         { AV_386_MON,                   "MON" },
 843         { AV_386_CX16,                  "CX16" },
 844         { AV_386_AHF,                   "AHF" },
 845         { AV_386_TSCP,                  "TSCP" },
 846         { AV_386_AMD_SSE4A,             "AMD_SSE4A" },
 847         { AV_386_POPCNT,                "POPCNT" },
 848         { AV_386_AMD_LZCNT,             "AMD_LZCNT" },
 849         { AV_386_SSSE3,                 "SSSE3" },
 850         { AV_386_SSE4_1,                "SSE4.1" },
 851         { AV_386_SSE4_2,                "SSE4.2" },
 852         { 0, NULL }
 853 };
 854
 855 private int
 856 doshn(struct magic_set *ms, int clazz, int swap, int fd, off_t off, int num,
 857     size_t size, off_t fsize, int *flags, int mach)
 858 {
 859         Elf32_Shdr sh32;
 860         Elf64_Shdr sh64;
 861         int stripped = 1;
 862         size_t nbadcap = 0;
 863         void *nbuf;
 864         off_t noff, coff;
 865         uint64_t cap_hw1 = 0;   /* SunOS 5.x hardware capabilites */
 866         uint64_t cap_sf1 = 0;   /* SunOS 5.x software capabilites */
 867
 868         if (size != xsh_sizeof) {
 869                 if (file_printf(ms, ", corrupted section header size") == -1)
 870                         return -1;
 871                 return 0;
 872         }
 873
 874         for ( ; num; num--) {
 875                 if (lseek(fd, off, SEEK_SET) == (off_t)-1) {
 876                         file_badseek(ms);
 877                         return -1;
 878                 }
 879                 if (read(fd, xsh_addr, xsh_sizeof) == -1) {
 880                         file_badread(ms);
 881                         return -1;
 882                 }
 883                 off += size;
 884
 885                 /* Things we can determine before we seek */
 886                 switch (xsh_type) {
 887                 case SHT_SYMTAB:
 888 #if 0
 889                 case SHT_DYNSYM:
 890 #endif
 891                         stripped = 0;
 892                         break;
 893                 default:
 894                         if (xsh_offset > fsize) {
 895                                 /* Perhaps warn here */
 896                                 continue;
 897                         }
 898                         break;
 899                 }
 900
 901                 /* Things we can determine when we seek */
 902                 switch (xsh_type) {
 903                 case SHT_NOTE:
 904                         if ((nbuf = malloc((size_t)xsh_size)) == NULL) {
 905                                 file_error(ms, errno, "Cannot allocate memory"
 906                                     " for note");
 907                                 return -1;
 908                         }
 909                         if ((noff = lseek(fd, (off_t)xsh_offset, SEEK_SET)) ==
 910                             (off_t)-1) {
 911                                 file_badread(ms);
 912                                 free(nbuf);
 913                                 return -1;
 914                         }
 915                         if (read(fd, nbuf, (size_t)xsh_size) !=
 916                             (ssize_t)xsh_size) {
 917                                 free(nbuf);
 918                                 file_badread(ms);
 919                                 return -1;
 920                         }
 921
 922                         noff = 0;
 923                         for (;;) {
 924                                 if (noff >= (off_t)xsh_size)
 925                                         break;
 926                                 noff = donote(ms, nbuf, (size_t)noff,
 927                                     (size_t)xsh_size, clazz, swap, 4,
 928                                     flags);
 929                                 if (noff == 0)
 930                                         break;
 931                         }
 932                         free(nbuf);
 933                         break;
 934                 case SHT_SUNW_cap:
 935                         if (nbadcap > 5)
 936                                 break;
 937                         if (lseek(fd, (off_t)xsh_offset, SEEK_SET) ==
 938                             (off_t)-1) {
 939                                 file_badseek(ms);
 940                                 return -1;
 941                         }
 942                         coff = 0;
 943                         for (;;) {
 944                                 Elf32_Cap cap32;
 945                                 Elf64_Cap cap64;
 946                                 char cbuf[/*CONSTCOND*/
 947                                     MAX(sizeof cap32, sizeof cap64)];
 948                                 if ((coff += xcap_sizeof) > (off_t)xsh_size)
 949                                         break;
 950                                 if (read(fd, cbuf, (size_t)xcap_sizeof) !=
 951                                     (ssize_t)xcap_sizeof) {
 952                                         file_badread(ms);
 953                                         return -1;
 954                                 }
 955                                 (void)memcpy(xcap_addr, cbuf, xcap_sizeof);
 956                                 switch (xcap_tag) {
 957                                 case CA_SUNW_NULL:
 958                                         break;
 959                                 case CA_SUNW_HW_1:
 960                                         cap_hw1 |= xcap_val;
 961                                         break;
 962                                 case CA_SUNW_SF_1:
 963                                         cap_sf1 |= xcap_val;
 964                                         break;
 965                                 default:
 966                                         if (file_printf(ms,
 967                                             ", with unknown capability "
 968                                             "0x%" INT64_T_FORMAT "x = 0x%"
 969                                             INT64_T_FORMAT "x",
 970                                             (unsigned long long)xcap_tag,
 971                                             (unsigned long long)xcap_val) == -1)
 972                                                 return -1;
 973                                         if (nbadcap++ > 2)
 974                                                 coff = xsh_size;
 975                                         break;
 976                                 }
 977                         }
 978                         break;
 979
 980                 default:
 981                         break;
 982                 }
 983         }
 984         if (file_printf(ms, ", %sstripped", stripped ? "" : "not ") == -1)
 985                 return -1;
 986         if (cap_hw1) {
 987                 const cap_desc_t *cdp;
 988                 switch (mach) {
 989                 case EM_SPARC:
 990                 case EM_SPARC32PLUS:
 991                 case EM_SPARCV9:
 992                         cdp = cap_desc_sparc;
 993                         break;
 994                 case EM_386:
 995                 case EM_IA_64:
 996                 case EM_AMD64:
 997                         cdp = cap_desc_386;
 998                         break;
 999                 default:
1000                         cdp = NULL;
1001                         break;
1002                 }
1003                 if (file_printf(ms, ", uses") == -1)
1004                         return -1;
1005                 if (cdp) {
1006                         while (cdp->cd_name) {
1007                                 if (cap_hw1 & cdp->cd_mask) {
1008                                         if (file_printf(ms,
1009                                             " %s", cdp->cd_name) == -1)
1010                                                 return -1;
1011                                         cap_hw1 &= ~cdp->cd_mask;
1012                                 }
1013                                 ++cdp;
1014                         }
1015                         if (cap_hw1)
1016                                 if (file_printf(ms,
1017                                     " unknown hardware capability 0x%"
1018                                     INT64_T_FORMAT "x",
1019                                     (unsigned long long)cap_hw1) == -1)
1020                                         return -1;
1021                 } else {
1022                         if (file_printf(ms,
1023                             " hardware capability 0x%" INT64_T_FORMAT "x",
1024                             (unsigned long long)cap_hw1) == -1)
1025                                 return -1;
1026                 }
1027         }
1028         if (cap_sf1) {
1029                 if (cap_sf1 & SF1_SUNW_FPUSED) {
1030                         if (file_printf(ms,
1031                             (cap_sf1 & SF1_SUNW_FPKNWN)
1032                             ? ", uses frame pointer"
1033                             : ", not known to use frame pointer") == -1)
1034                                 return -1;
1035                 }
1036                 cap_sf1 &= ~SF1_SUNW_MASK;
1037                 if (cap_sf1)
1038                         if (file_printf(ms,
1039                             ", with unknown software capability 0x%"
1040                             INT64_T_FORMAT "x",
1041                             (unsigned long long)cap_sf1) == -1)
1042                                 return -1;
1043         }
1044         return 0;
1045 }
1046
1047 /*
1048  * Look through the program headers of an executable image, searching
1049  * for a PT_INTERP section; if one is found, it's dynamically linked,
1050  * otherwise it's statically linked.
1051  */
1052 private int
1053 dophn_exec(struct magic_set *ms, int clazz, int swap, int fd, off_t off,
1054     int num, size_t size, off_t fsize, int *flags, int sh_num)
1055 {
1056         Elf32_Phdr ph32;
1057         Elf64_Phdr ph64;
1058         const char *linking_style = "statically";
1059         const char *shared_libraries = "";
1060         unsigned char nbuf[BUFSIZ];
1061         ssize_t bufsize;
1062         size_t offset, align;
1063
1064         if (size != xph_sizeof) {
1065                 if (file_printf(ms, ", corrupted program header size") == -1)
1066                         return -1;
1067                 return 0;
1068         }
1069
1070         for ( ; num; num--) {
1071                 if (lseek(fd, off, SEEK_SET) == (off_t)-1) {
1072                         file_badseek(ms);
1073                         return -1;
1074                 }
1075
1076                 if (read(fd, xph_addr, xph_sizeof) == -1) {
1077                         file_badread(ms);
1078                         return -1;
1079                 }
1080
1081                 off += size;
1082
1083                 /* Things we can determine before we seek */
1084                 switch (xph_type) {
1085                 case PT_DYNAMIC:
1086                         linking_style = "dynamically";
1087                         break;
1088                 case PT_INTERP:
1089                         shared_libraries = " (uses shared libs)";
1090                         break;
1091                 default:
1092                         if (xph_offset > fsize) {
1093                                 /* Maybe warn here? */
1094                                 continue;
1095                         }
1096                         break;
1097                 }
1098
1099                 /* Things we can determine when we seek */
1100                 switch (xph_type) {
1101                 case PT_NOTE:
1102                         if ((align = xph_align) & 0x80000000UL) {
1103                                 if (file_printf(ms,
1104                                     ", invalid note alignment 0x%lx",
1105                                     (unsigned long)align) == -1)
1106                                         return -1;
1107                                 align = 4;
1108                         }
1109                         if (sh_num)
1110                                 break;
1111                         /*
1112                          * This is a PT_NOTE section; loop through all the notes
1113                          * in the section.
1114                          */
1115                         if (lseek(fd, xph_offset, SEEK_SET) == (off_t)-1) {
1116                                 file_badseek(ms);
1117                                 return -1;
1118                         }
1119                         bufsize = read(fd, nbuf, ((xph_filesz < sizeof(nbuf)) ?
1120                             xph_filesz : sizeof(nbuf)));
1121                         if (bufsize == -1) {
1122                                 file_badread(ms);
1123                                 return -1;
1124                         }
1125                         offset = 0;
1126                         for (;;) {
1127                                 if (offset >= (size_t)bufsize)
1128                                         break;
1129                                 offset = donote(ms, nbuf, offset,
1130                                     (size_t)bufsize, clazz, swap, align,
1131                                     flags);
1132                                 if (offset == 0)
1133                                         break;
1134                         }
1135                         break;
1136                 default:
1137                         break;
1138                 }
1139         }
1140         if (file_printf(ms, ", %s linked%s", linking_style, shared_libraries)
1141             == -1)
1142             return -1;
1143         return 0;
1144 }
1145
1146
1147 protected int
1148 file_tryelf(struct magic_set *ms, int fd, const unsigned char *buf,
1149     size_t nbytes)
1150 {
1151         union {
1152                 int32_t l;
1153                 char c[sizeof (int32_t)];
1154         } u;
1155         int clazz;
1156         int swap;
1157         struct stat st;
1158         off_t fsize;
1159         int flags = 0;
1160         Elf32_Ehdr elf32hdr;
1161         Elf64_Ehdr elf64hdr;
1162         uint16_t type, phnum, shnum;
1163
1164         if (ms->flags & (MAGIC_MIME|MAGIC_APPLE))
1165                 return 0;
1166         /*
1167          * ELF executables have multiple section headers in arbitrary
1168          * file locations and thus file(1) cannot determine it from easily.
1169          * Instead we traverse thru all section headers until a symbol table
1170          * one is found or else the binary is stripped.
1171          * Return immediately if it's not ELF (so we avoid pipe2file unless needed).
1172          */
1173         if (buf[EI_MAG0] != ELFMAG0
1174             || (buf[EI_MAG1] != ELFMAG1 && buf[EI_MAG1] != OLFMAG1)
1175             || buf[EI_MAG2] != ELFMAG2 || buf[EI_MAG3] != ELFMAG3)
1176                 return 0;
1177
1178         /*
1179          * If we cannot seek, it must be a pipe, socket or fifo.
1180          */
1181         if((lseek(fd, (off_t)0, SEEK_SET) == (off_t)-1) && (errno == ESPIPE))
1182                 fd = file_pipe2file(ms, fd, buf, nbytes);
1183
1184         if (fstat(fd, &st) == -1) {
1185                 file_badread(ms);
1186                 return -1;
1187         }
1188         fsize = st.st_size;
1189
1190         clazz = buf[EI_CLASS];
1191
1192         switch (clazz) {
1193         case ELFCLASS32:
1194 #undef elf_getu
1195 #define elf_getu(a, b)  elf_getu32(a, b)
1196 #undef elfhdr
1197 #define elfhdr elf32hdr
1198 #include "elfclass.h"
1199         case ELFCLASS64:
1200 #undef elf_getu
1201 #define elf_getu(a, b)  elf_getu64(a, b)
1202 #undef elfhdr
1203 #define elfhdr elf64hdr
1204 #include "elfclass.h"
1205         default:
1206             if (file_printf(ms, ", unknown class %d", clazz) == -1)
1207                     return -1;
1208             break;
1209         }
1210         return 0;
1211 }
1212 #endif